Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Can you define striated cardiac muscle tissue, Q. Of which kind of tissue i...

Q. Of which kind of tissue is the heart made? How is this tissue oxygenated and nutrified? The heart is made of striated cardiac muscle tissue and the heart muscle is called th

Define isotope dilution method, Define Isotope Dilution Method? The mea...

Define Isotope Dilution Method? The measurement of total body water (TBW) is based on the principle of hydrometry. You must be aware that water is the most abundant substance i

Explain acid butt - carbohydrate utilization pattern test, Acid butt - carb...

Acid butt - carbohydrate utilization pattern test ? Acid butt (yellow) and acid slant (yellow) with or without gas production – Glucose along with lactose and/or sucrose, is deg

Concomitant caroid endarterectomy and cabg, Concomitant caroid endarterecto...

Concomitant caroid endarterectomy and CABG :   Symptoimatic or asymptomatic carotid artery disease may be present in patients undergoing CABG. It is very important to recognize thi

Define multiple tube fermentation test, Define Most Probable Number Test (M...

Define Most Probable Number Test (Multiple Tube Fermentation Test)? Presence of coliforms in the water sample can be detected by performing multiple tube fermentation test whic

Explain the uses of hydrocolloids, Explain the uses of hydrocolloids In...

Explain the uses of hydrocolloids In particular, hydrocolloids can provide water for increasing the flexibility (plasticizing) of other food components. These can also affect i

Explain about microbial polysaccharides, Microbial polysaccharides Many...

Microbial polysaccharides Many microorganisms produce polysaccharides that either remain attached to the cell wall (capsular polysaccharides) or are  secreted into the extracel

Properties of isozymes, Properties of Isozymes Isozymes differ from  ...

Properties of Isozymes Isozymes differ from  each other not only in  the amino acid composition, they also have different electrophoretic property, thermolability, immunologi

Define the contraceptive morbidity, Define the Contraceptive Morbidity ...

Define the Contraceptive Morbidity Contraceptive morbidity, which covers any condition that result from efforts (other than abortion) to limit fertility, whether they are tradi

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd